There are generally two types of automobile transmissions for changing the ratio (hereafter called gear ratio) of power flow from the engine to the drive axle. One is the manually operated gear-shift type which is used with a disc type clutch, and the other is the automatic type provided with a hydraulic torque converter and a planetary gear system. Both types of transmission have been conventionally used but each has its distinct disadvantages. Conventional manual transmissions require a certain level of skill to be operated efficiently and conventional automatic transmissions are energy consuming, bulky and expensive to manufacture.
In view of the aforesaid disadvantages of conventional automobile transmissions, the present invention offers a novel automatic gear shifting device for operating a gear-shift type transmission in conjunction with a disc type clutch for an automobile, in which the gear-shifting operation may be selectively operated automatically or manually and in which less energy is consumed and the cost of manufacture is less than conventional automatic transmissions.